Refrigerator-compressor system with wet weather adjustment

ABSTRACT

A refrigerator-compressor system comprised of several independent refrigerator compressor units housed within a common outdoor housing, and connected to remotely located refrigerator cabinets or rooms by means of hot and cold refrigerant circulation lines. The refrigerator-compressor system automatically adjusts to cold outdoor temperatures, so that lowtemperature malfunctioning is avoided. The separate refrigeratorcompressor units, being independently responsive to different refrigerator cabinet conditions, will almost always have at least one refrigerator-compressor unit operating and supplying heat to the interior of the housing. This heat is dissipated to the outdoors by air circulating from beneath and through side louvres, except when the temperature drops sufficiently low to cause refrigerator-compressor operating problems. At low temperatures, a motor responsive to outdoor temperature closes the side louvres of the housing and the heat produced by operation of any one of the several refrigerator-compressor units serves to warm all the nonoperating units, so that they are ready to go into immediate operation when refrigeration demand is made upon them.

United States Patent [72] lnventors Arnold S. Kaufman;

Albert Sweet. both of Los Angles, Calif.

[21] Appl. No. 811,855

[22] Filed Apr. 1,1969

[45] Patented June 15, 1971 [73] Assignee Elsters Hollywood, Calif.

[54] REFRIGERATOR-COMPRESSOR SYSTEM WITH WET WEATHER ADJUSTMENT 6 Claims, 5 Drawing Figs. [52] 11.8. CI 62/183, 62/180, 62/506 [51] Int. Cl F25b 39/04 [50] Field ofSearch 62/183, 184,180,181, 182

[56] References Cited UNITED STATES PATENTS 2,958,208 11/1960 Braden .f. 62/181 3,004,402 10/1961 Dart 62/184 3,138,941 6/1964 Jensen..... 62/184 3,148,514 9/1964 Mathis..... 62/183 3,205,674 9/1965 Arnold 62/180 3,242,686 3/1966 Bowman ABSTRACT: A refrigerator-compressor system comprised of several independent refrigerator compressor units housed within a common outdoor housing, and connected to remotely located refrigerator cabinets or rooms by means of hot and cold refrigerant circulation lines. The refrigerator-compressor system automatically adjusts to cold outdoor temperatures, so that low-temperature malfunctioning :is avoided. The separate refrigerator-compressor units, being independently responsive to different refrigerator cabinet conditions, will almost always have at least one refrigerator-compressor unit operating and supplying heat to the interior of the housing. This heat is dissipated to the outdoors by air circulating from beneath and through side louvres, except when the: temperature drops sufficiently low to cause refrigerator-compressor operating problems. At low temperatures, a motor responsive to outdoor temperature closes the side louvres of the housing and the heat produced by operation of any one of the several refrigerator-compressor units serves to warm all the nonoperating units, so that they are ready to go into immediate operation when refrigeration demand is made upon them.

REFRIGERATOR-COMPRESSOR SYSTEM WITH WET WEATHER ADJUSTMENT This invention relates generally to large refrigeration systems such as those found in restaurants, hotels, food markets, and public institutions with large kitchens; more particularly, it relates to an electrically powered refrigerator-compressor system, located out of doors, which supplies a plurality of independently responsive refrigerator-compressor units contained within a single housing, in combination with louvre means which automatically adjust to admit or exclude outdoor air, to maintain suitable operating temperatures for the refrigerator-compressor unit within the common housing.

The present invention is concerned, in its typical application, with a refrigeration system in which large refrigerator rooms, or refrigerator cabinets, are located inside of a restaurant building, for example, and are connected by pipes or tubing for the circulation of refrigerant fluid to and from a refrigerator-compressor system remotely located outside of the building, on its roof, for example. The invention is entirely concerned with refrigerator systems which rely upon an intermittently operated compressor for producing the refrigeration required. Almost always, the outdoor refrigerator-compressor unit is comprised of an electric motor and compressor housed together in a sealed housing, a system of air-cooled coils for cooling the refrigerant fluid immediately after compression, an electrically powered fan for directing a stream of air over the cooling coils, a suitable refrigerant-circulating system, and a suitable temperature instrumentation system for starting and stopping the compressor according to refrigeration demands indicated indoors inside the refrigerator cabinet or room. Such systems have demonstrated their usefulness and reliability and for many years have been by far the most commonly used refrigeration systems for commercial and institutional installations.

However, the refrigerator-compressor system just described has frequently proven less reliable than thennal refrigeration systems (such as those relying on a gas flame) in geographic areas in which the outdoor ambient air temperature occasionally fell below the temperature required inside of the refrigerator box. Where such cold weather conditions are encountered, the compressor-powered refrigerator system may simply refuse to start when the next demand for refrigeration is signaled by the refrigerator's instrumentation system.

Furthermore, refrigeratorcompressors exposed to cold weather have proven vulnerable to malfunctioning which damages the equipment or fails to provide the correct tem perature at the refrigerator box location. For example, liquid refrigerant sometimes accumulates inside the compressor, so that when it starts, there is a tendency to slug liquid refrigerant. Another source of difficulty is that a refrigeration system, including its associated instrumentation, tend to function erratically, and to be unable to maintain a reasonably constant refrigeration temperature at the refrigerator compartment, during periods when outdoor ambient air temperature is colder than the design conditions which prevail most of the time.

Additionally, and aside from any difficulties in the refrigerator-compressor system itself, the associated instrumentation is subject to malfunction if exposed to blasts of cold air, particularly when such air carries entrained rain or snow.

Where the installation achieves its cooling by means of water towers and circulating water, or the like, or where some other type of refrigeration other than refrigerator-compressor refrigeration is employed, various expedients have been devised to avoid the malfunction and breakdown problems described above.

Also, in the past, refrigeration engineers have resorted to expensive special buildings and equipment to insure reliability in refrigerator-compressors exposed to the outdoor air in cold weather climates.

Typically, in previously known installations, a single large refrigerator-compressor system has been matched to a refrigerator box remotely inside an adjacent building. For several refrigerator compartments, several outdoor refrigerator-compressor systems, independent of each other except for a common electrical power source, have been employed. In a typical installation, one such refrigerator compartment might be a room in constant use, with the door frequently opened by employees to introduce or remove food; each door opening would be accompanied by a loss of refrigeration and the introduction of heated air from the interior of the building into the interior of the refrigerator compartment; for such a refrigerator, the remote refrigerator-compressor would be started and stopped so often that that would be less likely than if starting and stopping were rare. In a second refrigerator compartment, however, use might be as infrequent as only a few times a day; with half a day or more, and an entire night of shutdown during a period of freezing weather, the outdoor refrigerator-compressor has proven quite vulnerable to failure or malfunctioning.

It is a major object of the present invention to avoid the cold weather malfunctioning of outdoor refrigeratorcompressor systems by housing several refrigerator-compressor modules, each with its own refrigeration demands, instrumentation, within a single housing, and providing the common housing with air circulation control automatically responsive to outdoor ambient air temperature It is an important object of the invention to combine several modules of refrigerator-compressor units in a single housing, which closes itself against the outdoor air during periods of low temperature, so that at least one refrigerator-compressor unit is almost always in operation within the common housing, thus providing heating, small in amount, but sufficient to prevent cold weather malfunctioning.

It is another object of the invention to provide a refrigerator-compressor system which automatically adjusts between the extreme variations of day and night and season to season, without requiring special servicing by refrigeration personnel either daily or seasonally.

Another important object is to provide a system which can protect itself against cold weather, but is also capable of providing for greatly increased air circulation, which is required during long periods of hot summer weather.

The foregoing and other objects and advantages of the invention will be understood from the following description of preferred specific embodiment, which is illustrated in the accompanying drawings, in which: FIG. 1 is a perspective view of a refrigerator-compressor system constructed according to the invention, the modular refrigerator-compressor units being indicated in dashed outline within the coacting, weather-responsive housing;

FIG. 2 is a perspective view of a typical single refrigeratorcompressor module;

FIG. 3 is a vertical sectional view through the automatically operated louvre system of the housing illustrated in FIG. 1, as viewed at the transverse vertical plane indicated in FIG. I by the arrow 3-3;

FIG. 4 is a plan view of the refrigerator-compressor system of FIG. 1, with the roof removed, and with substantial simplification of detail not required for purposes of explaining the invention; and

FIG. 5 is a wiring diagram of the operating motors and instrumentation which open the side louvres of the refrigeratorcompressor housing during periods of sufficiently warm outdoor temperatures, and close them when outdoor temperatures become too low for the proper functioning of the refrigerator-compressor modules.

In FIG. 1, the refrigerator-compressor system is indicated in its entirety by the numeral 10, as appears mounted on the roof 11 of a restaurant or similar commercial or institutional bu ilding. A suitable platform K2 is illustrated to indicate a loadbearing, weatherproof, and possibly fireproof part of roof 11, intended to support the refrigerator-compressor system 10. For purposes of describing this typical application, the system 10 is shown as comprised of three substantially identical housing modules 13, 14, and 15. In the typical construction illustrated, each of the modules 13, M and 15, contains four refrigerator-compressor modules (as single one being seen in FIG. 2). As shown, the modules 20 are supported in two levels, two modules on a lower rack 16 and two modules on an upper rack 17.

In the preferred construction illustrated, all the housing modules 13, 14 and 15, are in open interior communication with each other, and are joined together to form a single housing which may be designated by the numeral 18.

It is an essential and important feature of the invention that the common housing 18 contains several of the modular units 20, rather than just one, and that these modular units are provided with independent refrigeration instrumentation, so that they do not have identical instance of refrigeration demand and identical periods of operation and shutdown.

Also, it is an important feature of the invention that the several modules 20 within the common housing 115 are supported on open racks 21, which are supported in turn on transverse angle irons 22, so that air within common housing 18 may freely circulate throughout the entire housing, with a minimum of restriction, and without obstruction by partitions, solid flooring, or the like. The common housing 18 is designed to function as either an enclosed housing (during periods of very cold weather) or as an open housing permitting the maximum movement of cooling outdoor air (during periods of hot weather, or at least temperatures higher than the minimums at which the refrigerator-compressor modules 20 can operate without danger of cold weather malfunction.

Housing 18 is provided with air circulation openings, which are covered by doors, and automatic motor and instrumentation means for closing said doors during periods of cold weather in order to convert housing 18 to an enclosed heatconserving chamber. In the preferred embodiment illustrated, each of the housing modules 13, 14 and 15 is supported on legs at a substantial elevation above the platform 12 so that outdoor air freely circulates through an underspace 26 underneath the modular housings. Also, since the platforms 21 are open grille structures, and there is no flooring in any of the modular units 13, 14 and 15, air from the underspace 26 freely moves upwardly into the interior of the common housing 18, whenever such circulation is permitted.

Horizontal passage of outdoor air through the modules 13, 14 and 15 is controlled by front and back louvre systems 31 and 32, which comprise substantially the entire front and back walls of each of the modular units 13, 14 and 15. Typically, the louvre systems 31 and 32 are identical, as are the corresponding front and back louvre systems of modular housing 13 and 14. Only louvre system 31 will be described in detail. It will be seen from the dashed outline in FIG. 11, viewed together with the transverse vertical sectional view of FIG. 3, that a louvre operating motor 35 is mounted on lower grill platforms 16 just inside of modular housing 15. In front of louvre motor 35, the louvre system 31 is seen to be comprised of a double frame 36 in which a large number of horizontally disposed louvres 37 are hingeably mounted by hinge mounts 38 at their upper edges.

During warm weather, or at least weather of moderate temperatures, the louvres 37 are held in an oblique outward position indicated in FIG. 3 by the dash line 40. The arrow 41 indicates the outward opening movement to open louvre position 40. The open louvre position is some oblique angle, suitable for the location and climate, such as degrees, so as to provide shade from the sun, and protection from rain, while permitting plentiful air circulation in a horizontal direction through the louvre openings indicated by the numeral 42. It will be understood that the louvre opening 42 cooperate with the underspace 26, and the natural upward movement of heated air from the refrigeration compressor module 20, to generate a circulating air current moving upwardly from under space 26 and then outwardly from either front louvres 31 or back louvres 32 depending on the direction of the prevailing winds, if any.

All the louvres 37 movably mounted in frame 36 are interconnected through a louvre linkage 45 comprised of main vertical bars 46 and individual louvre bars 47, all connected to each other and to the louvres typically by pivot pins 48. The entire louvre linkage 45 is movable, together with the louvres 37, by motor 35 acting through a motor linkage 50, comprised ofa crank arm 51 and a reciprocating link 52. Arm 51 and link 52 are pivotally connected to each other at 53, and the upper end of reciprocating link 52 is pin connected at 54 to the louvre linkage 45.

Although various modes of operation may be used within the scope of the invention, a typical preferred construction is illustrated in FIG. 3, showing that the motor 35, when actuated by cold weather, raises arm 51 in a counterclockwise direction so that the louvres 37 assume the closed position illustrated in FIG. 3. When, however, outdoor ambient air is at a sufficiently high temperature, for example, above 30 F., the motor 35, either by actuation or by shutoff and the operation of gravity, permits crank arm 51 to rotate in the direction indicated by the arrow 55, dropping reciprocating link 52 and the louvre linkage 45, so that louvres 37 swing to the open louvre position 40. It will be appreciated that the particular opening devices are many, well known to those familiar with the several motor and temperature responsive instrumentation art, and may be such as to adjust louvres 37 to many intermediate positions corresponding to the temperature if desired.

A typical wiring diagram is that illustrated in FIG. 5, in which power to the motor 35 is provided from a power source 60 through electrical wiring 61, and through a temperature controller switch 62, he latter closing only when it is permitted to do so by a low-temperature-sensing bulb 63, which may be mounted in any suitable location on the exterior of the common housing 18 for the refrigerator-compressor system 10. Bulb 63 is connected to the controller switch 62 by suitable transmission conduit 64.

The plan view of FIG. 4 reveals an additional advantage of the preferred form of the invention shown in the drawing. Each of the refrigerator-compressor modules 20 (FIG. 2) has its own pair of refrigerant circulation lines 71 and 72 independent of the refrigerant circulation lines of every other module. Each pair of refrigerant circulation lines 71 and 72 is connected to a particular evaporating unit at the refrigerator com partment. Moreover, refrigeration demands at the compartment can be signalled to the module 20 simply by the state of the refrigerant fluid returning to module 20 in the hot fluid return line, so that no independent wiring instrumentation is necessary. As shown in FIGS. 2 and 4, the several refrigerant lines 71 and 72 are directed to a standard location and grouped with other refrigerant lines as 73 and 74, which are then clustered at a standard line of mounting as indicated in 75, within the housing modules 13 to 15, all lines being brought down through the platform 12 at a single central location indicated in FIG. 4 by the numeral 76. Using the refrigeration-compressor system of the invention, it is possible to prefabricate many of the modules 20 and the housings 13 to 15, utilizing sizes for refrigeration-compressor 20 small enough so that several of the modules 20 will usually be required in a minimum size of commercial or institutional jobs for which this type of installation is intended. For each particular installation, some balancing of engineering factors, local climatic factors, and economics will be required to select the number of modules 20, and the size per module. Whatever this balance, however, at least two modules 20 and preferably substantially more than that, will be housed within a single housing 18, and the different modules connected to different refrigerator compartment locations, likely to have different timing and frequency of demand. With the invention illustrated and described here, the modules 20 can be planned to make it highly unlikely that all remain shut down for a prolonged period of time. Instead, it can be made quite certain that, regardless of how cold the outside temperatures may be within the known range of temperature conditions for the location, not more than a few hours at most pass without one of the modules being turned on by virtue of a refrigeration demand, thus supplying heat from the condenser coil 20b, and the compressor and the motor combination 20a. The fan 200 will distribute the heat through the entire interior space of the entire housing 18. During the period of cold weather, all the louvres systems 31 and 32 will be tightly closed. Although the housing 18 will continue to be open at the bottom to the exposed underspace 26, heat will not be lost rapidly by convection, since the relatively warm air inside of common housing 18 will tend to remain captive in an enclosure open only at the bottom. Of course, since the roof 80 of the housing 18 is uninsulated sheetmetal, heat will not be retained for any great length of time, but this is not the purpose of the system and it is not necessary. The entire point of the invention, and the novelty of it is that with great simplicity and ruggedness, and proper balancing of several modular units of refrigerator-compressor 20 within a common housing, coacting with controlled air circulation through louvres 37, a system is provided which is immune to the usual cold weather malfunctioning of compressor-refrigeration systems, and yet requires no special construction or adjustment from one time of the year to another. Indeed, the identical unit adapted to survive through cold weather construction, as illustrated by refrigerator-compressor system 10, can be manufactured on a standard basis and installed even in hot weather climates. The provision against cold weather failure will never come into play but neither will it cause any difficulty in the operation of the system in the continuous warm weather location.

We claim:

1. In a refrigeration system in which a refrigerated zone comprised of at lease one compartment is supplied with circulating refrigerant from a remotely located outdoor refrigerator-compressor system, in which the refrigerator-compressor system operates intermittently in response to demand for refrigeration from said refrigeration zone, a refrigerator-compressor system which includes:

a plurality of mutually independent refrigerator-compressor systems, each including its own refrigerator-compressor module at said remote outdoor location, its own refrigerant circulation system communicating with said refrigeration zone, and its own refrigeration-demandsensing system communicating with said refrigeration zone to produce intermittent operation of said module in response to a refrigeration demand from said zone;

a common housing enclosing said plurality of refrigeratorcompressor modules, said housing enclosing a common air space with free circulation of air within said housing between said refrigerator-compressor modules;

a system of air circulation openings with movable covering means in the walls of said housing to regulate the circulation of air through said housing byway of said air circula tion openings;

and outdoor-temperature-sensing means combined with operating means for shifting said covering means between open and closed positions in response to outdoor temperature conditions.

2. A refrigerator-compressor system as described in claim 1, in which said housing is supported at an elevation above a supporting surface to provide an underspace in open communica tion with outdoor air, and the interior of said housing is in open communication with said underspace through the bottom of said housing; and said air circulation opening and movable cover means are constructed in the form of sidewall openings in said housing provided with horizontal louvres hinged along their upper edges, and movable between a vertical closed position and an oblique open position in response to operation by said outdoor-air-sensing means.

3. A refrigerator-compressor system as described in claim 1 in which at least two of said refrigerator-compressor modules are connected by their respective refrigeration-demandsensing means to parts of said refrigeration zones characterized by very different timing of refrigeration demand.

4. A refrigerator-compressor system as described in claim 1 in which said refrigerator-compressor modules are connected to said refrigeration zones only by said refrigerant circulation system, and refrigeration demand from said zone is transmitted to at least some of said modules only by the physical property of the refrigerant fluid circulating in the refrigerant circulation system of said module.

5. A refrigerator-compressor system as described in claim 1 in which at least two of said refrigerator-compressor modules incorporates its own heat-liberating condenser, an its own air circulation fan for circulating air within said common housing over said condenser and back to the interior of said common housing.

6. A refrigerator-compressor system as described in claim 1 in which said outdoor-temperature-sensing means includes a cover opening motor which begins to close said covers when outdoor air reaches a freezing temperature, and the degree of closure is in proportion to the degree by which the outdoor air drops below freezing temperature. 

1. In a refrigeration system in which a refrigerated zone comprised of at lease one compartment is supplied with circulating refrigerant from a remotely located outdoor refrigerator-compressor system, in which the refrigeratorcompressor system operates intermittently in response to demand for refrigeration from said refrigeration zone, a refrigeratorcompressor system which includes: a plurality of mutually independent refrigerator-compressor systems, each including its own refrigerator-compressor module at said remote outdoor location, its own refrigerant circulation system communicating with said refrigeration zone, and its own refrigeration-demand-sensing system communicating with said refrigeration zone to produce intermittent operation of said module in response to a refrigeration demand from said zone; a common housing enclosing said plurality of refrigeratorcompressor modules, said housing enclosing a common air space with free circulation of air within said housing between said refrigerator-compressor modules; a system of air circulation openings with movable covering means in the walls of said housing to regulate the circulation of air through said housing by way of said air circulation openings; and outdoor-temperature-sensing means combined with operating means for shifting said covering means between open and closed positions in response to outdoor temperature conditions.
 2. A refrigerator-compressor system as described in claim 1, in which said housing is supported at an elevation above a supporting surface to provide an underspace in open communication with outdoor air, and the interior of said housing is in open communication with said underspace through the bottom of said housing; and said air circulation opening and movable cover means are constructed in the form of sidewall openings in said housing provided with horizontal louvres hinged along their upper edges, and movable between a vertical closed position and an oblique open position in response to operation by said outdoor-air-sensing means.
 3. A refrigerator-compressor system as described in claim 1 in which at least two of said refrigerator-compressor modules are connected by their respective refrigeration-demand-sensing means to parts of said refrigeration zones characterized by very different timing of refrigeration demand.
 4. A refrigerator-compressor system as described in claim 1 in which said refrigerator-compressor modules are connected to said refrigeration zones only by said refrigerant circulation system, and refrigeration demand from said zone is transmitted to at least some of said modules only by the physical property of the refrigerant fluid circulating in the refrigerant circulation system of said module.
 5. A refrigerator-compressor system as described in claim 1 in which at least two of said refrigerator-compressor modules incorporates its own heat-liberating condenser, an its own air circulation fan for circulating air within said common housing over said condenser and back to the interior of said common housing.
 6. A refrigerator-compressor system as described in claim 1 in which said outdoor-temperature-sensing means includes a cover opening motor which begins to close said covers when outdoor air reaches a freezing temperature, and the degree of closure is in proportion to the degree by which the outdoor air drops below freezing temperature. 